A great video lecture conducted by experienced physics teacher on 9th class physics chapter 2 topic2.1 graphical analysis. Get full understanding or ask any questions.
Graphical Analysis, ch 2, lec 2.5, Graphical Analysis - 9th Class Physics
27:40
Acceleration due to gravity, ch 2, lec 2.5, Graphical Analysis - 9th Class Physics
20:35